After Global Warming has disappeared into thin air, now *the* symbol of AGW, the 'Hockey stick' graph my Mann et al. is now rapidly dissipating into the ether as well.
The blog 'Watt's up with that' has an important item up: Ding dong the stick is dead. The infamous 'Hockey stick' graph that has been used by the UN's climate panel IPCC has always been suspect. And in fact has has severe credibility issues for some time now (see here, for instance).
But now it turns out the issues with the 'analysis' done by Mann et al. are even more severe then imagined. In fact, it begs the question whether climate science in particular, and science in general, will ever recover any of its former hallowed status of objective, independent and trustworthy.
To put the story as short and concise as I can: Mann et al. made a global temperature reconstruction using tree rings as indicators (proxies) of historical temperatures. In simple terms: A tree shows broader rings in warmer years, because it grows more in such years. For analysis, series of observations from different trees from the same site are combined in a so-called chronology. Generally it is accepted that for a reliable chronology you need at least 10 and preferably (a lot) more trees.
Steve McIntyre, one of the two original debunkers of the Hockey stick, managed to get his hands on some of the data used by Mann et al. As it turns out, the blade portion of the hockey stick graph can be attributed to a single chronology consisting of just 10 trees.
A bit on the thin side, you might say, but if they don't have a larger sample you have to make due, don't you? Well, yes. However, McIntyre found that far from having a sample of just 10 trees, the actual sample consisted of 34 trees. What's more, the 10 trees used in the sample seem to be pre-selected to produce the blade portion of the hockey stick. McIntyre did an analysis using the trees left out of the sample and found another blade: This one turned down, not up as in the Mann et al. analysis (See graph above. In red the Mann et al. series, in black the other series and in green the mean of both).
Steve McIntyre comments: 'I hardly know where to begin in terms of commentary on this difference.' As the green line in the graph shows: The last 10-15 years were not (repeat: not) the hottest period in the last 2000 years.
Go on over and read the whole thing. It is a bit on the technical side, but the fraud (yes, I am going to use that word) shines through in sickly bright colors. It seems that out of 34 trees, Mann et al. selected 10 trees that together would suggest a massive warming in the last 20 years. Trees that suggested the opposite were left out of the sample. On purpose, it seems, in what would be a gross violation of one of the most basic principles of doing science.
This is a serious indictment of Mann et al., the IPCC, the UN and global warming 'science'. By rights, the graph reproduced above should mean the decisive blow to the whole AGW 'climate change' narrative. And by rights the perpetrators of this staggering piece of scientific fraud should be terminated. And I am not sure whether I mean that literally or not, either. At the end of this saga it may well turn out that these jokers have damned the scientific community as a whole into irrelevance. What started out with Galileo, Kepler and Newton and has brought Western civilization its unsurpassed success will have come to a bitter and sleazy end. The demise of science indeed.